.log{
    position: absolute;
    top: 20px;
    right: 10px;
    font-size: 50px;
}
.background{
    height: 1800px;
}
.line {
    z-index: -1;
    height: 350px;
    width: 5px;
    border: none;
    background-color: #fff;
}

.box {
    padding: 0 15%;
    font-size: 25px;
}

.box>.title {
    font-family: myFirstFont;
    margin:30px 0;
    font-size: 100px;
}

.connect {
    width: 80%;
    display: flex;
    justify-content: space-around;
    height: 400px;
    margin: 60px 0;
}
.item {
    padding-left: 50px;
    margin: 150px 0;
    display: flex;
    align-items: center;
    width: 70%;
    justify-content: space-around;
}
.item>div>video {
    display: flex;
    align-self: center;
    width: 250px;
    padding-right: 100px;
}
.item>div>img{
    display: flex;
    align-self: center;
    width: 500px;
}
.item .text {
    display: flex;
    flex-direction: column;
    line-height: 40px;
    width: 500px;
    text-indent: 2em;
}

.item .text .top {
    font-size: 40px;
    text-align: end;
    padding-right: 2em;
    margin-bottom: 20px;
}



/* 侧栏 */
.nav ul {
    list-style: none;
    cursor: pointer;
}

.nav ul li {
    border-bottom: 1px solid white;
}

.nav {
    position: fixed;
    top: 100px;
    width: 200px;
    height: 650px;
    background-color: #2b2b2b;
    opacity: 0.8;
}

.menus {
    margin: 50px 0;  
    padding-left: 0px;
    color: #fff;
}
.menus a{
    color: #fff;
}

.li {
    padding: 20px 0;
    letter-spacing: 2px;
    font-size: 17px;
    font-weight: 600;
    transition: 0.3s;
}

.menus li:hover {
    background-color: #201f1f;
}

.li .fa {
    font-size: 20px;
    width: 50px;
    height: 20px;
    text-align: center;
    margin-left: 5px;
}

.li ul {
    width: 0;
    padding: 50px 0;
    background-color: #1f1e1e;
    position: absolute;
    top: 0;
    right: 0;
    overflow: hidden;
    transition: 0.3s;
}

.li ul li {
    padding: 16px 24px;
    white-space: nowrap;
    transition: 0.3s;
}

.li:hover ul {
    width: 150px;
}

.li ul li:hover {
    background-color: #201f1f;
}
